Blocking histone deacetylation in Arabidopsis induces pleiotropic effects on plant gene regulation and development.
Blocking histone deacetylation in Arabidopsis induces pleiotropic effects on plant gene regulation and development.
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DOI：
10.1073/pnas.98.1.200
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发表时间：
2001-01
影响因子：
11.1
通讯作者：
L. Tian;Zengjian J Chen
中科院分区：
文献类型：
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作者：
L. Tian;Zengjian J Chen
组蛋白乙酰化和去乙酰化在真核基因调控中起着至关重要的作用。核心组蛋白的可逆修饰由组蛋白乙酰转移酶和组蛋白脱乙酰基酶(HD)两种内源性酶催化。总体而言，组蛋白去乙酰化与转录基因沉默有关，而乙酰化与基因激活相关。我们获得了表达反义拟南芥HD(AtHD1)基因的转基因植株。AtHD1是酵母中人类HD1和RPD3全球转录调控因子的同源物。反义AtHD1的表达导致内源性AtHD1转录显著减少，导致乙酰化的组蛋白积累，尤其是四乙酰化的H4。AtHD1表达和AtHD1合成的减少以及乙酰化谱的改变与多种发育异常有关，包括早期衰老、沉默基因的异位表达、顶端优势的抑制、同源异型变化、异时向幼化的转变、花缺陷以及雄性和雌性不育。一些表型可以归因于组织特异性基因(如超人)在营养组织中的异位表达。转基因植株中没有检测到基因组DNA甲基化的变化。这些结果表明，AtHD1是一个全球调控因子，在植物发育过程中通过DNA序列无关或表观遗传机制控制基因表达。除了DNA甲基化，组蛋白修饰可能参与了植物可塑性和自然界变异的一般调控机制。
Histone acetylation and deacetylation play essential roles in eukaryotic gene regulation. Reversible modifications of core histones are catalyzed by two intrinsic enzymes, histone acetyltransferase and histone deacetylase (HD). In general, histone deacetylation is related to transcriptional gene silencing, whereas acetylation correlates with gene activation. We produced transgenic plants expressing the antisense Arabidopsis HD (AtHD1) gene. AtHD1 is a homolog of human HD1 and RPD3 global transcriptional regulator in yeast. Expression of the antisense AtHD1 caused dramatic reduction in endogenous AtHD1 transcription, resulting in accumulation of acetylated histones, notably tetraacetylated H4. Reduction in AtHD1 expression and AtHD1 production and changes in acetylation profiles were associated with various developmental abnormalities, including early senescence, ectopic expression of silenced genes, suppression of apical dominance, homeotic changes, heterochronic shift toward juvenility, flower defects, and male and female sterility. Some of the phenotypes could be attributed to ectopic expression of tissue-specific genes (e.g., SUPERMAN) in vegetative tissues. No changes in genomic DNA methylation were detected in the transgenic plants. These results suggest that AtHD1 is a global regulator, which controls gene expression during development through DNA-sequence independent or epigenetic mechanisms in plants. In addition to DNA methylation, histone modifications may be involved in a general regulatory mechanism responsible for plant plasticity and variation in nature.